Four German NGOs have been accused of using covert methods to mislead Greek and European Union border forces to help smuggle migrants into Greece.

Mare Liberum, Sea Watch, FFM, and Josoor International Solidarity are all mentioned in the police investigation as having members or volunteers who have helped people smugglers in Turkey. They have been operating in Greece since the height of the migrant crisis in 2015, newspaper Proto Thema reports.

According to the newspaper, members of the NGOs mapped the movements of migrant boats leaving the Turkish mainland for the Greek island of Lesbos and used espionage and other methods to mislead Greek border forces as well as the European Union border agency Frontex.

The activists are also said to have recorded telecommunications conversations of Greek officials and manipulated the emergency number used by migrants when they are in distress.

Greek authorities have spent months conducting investigations into the activity of the NGOs and even managed to find maps on a ship belonging to Mare Liberum which detailed the points of exit for migrants along the Turkish coast and points on Lesbos for them to sail to.

Along with searches, seizures, and surveillance, investigators sent a group of agents to pose as migrants in July in Turkey to have an inside look at how the people trafficking scheme worked.

The insider agents said that two women, an Austrian national who is a founding member of Josoor International Solidarity and a Norwegian national, were in direct contact with people smugglers.

Greek police state that the organisations worked with the charity Alarmphone, which gave the NGOs the positions of the migrant boats which they used to allegedly help guide the vessels away from Greek border authorities.

While investigators have gathered evidence, which eventually led to the implication of over 30 NGO workers in late September, they have had much more difficulty tracking the cash flow of the organisations as they are all based in Germany, despite operating in Greece.

The Greek Financial Police, with the assistance of the National Transparency Authority, is expected to request help from Germany to determine if the NGOs under investigation took money from people traffickers.

The Greek investigation comes after several other countries have claimed that migrant taxi NGOs have links with people traffickers including a German report that stated smugglers track NGO ships off the coast of Libya.

“In the presence of NGO ships, concerted departures from Libya were noted. According to refugees and migrants, smugglers use the tracking function on various websites to determine the location of NGO ships and contacted them in individual cases using a satellite phone,” a German Joint Analysis and Strategy Centre for Illegal Migration (Gasim) report said earlier this year.

Follow Chris Tomlinson on Twitter at @TomlinsonCJ or email at ctomlinson(at)breitbart.com